FILE - In this April 12, 1999 file photo, Dr. Richard Rockefeller speaks at a news conference in Portland, Maine, about his family's pledge of $3.2 million to the Maine chapter of the Nature Conservancy for its purchase of land on the Upper St. John River. A family spokesman said Rockefeller was killed Friday, June 13, 2014, after crashing his small plane near the Westchester County Airport in Purchase, N.Y. Richard Rockfeller, of Falmouth, Maine, was a great grandson of Standard Oil co-founder John D. Rockefeller.
Photo: Robert F. Bukaty, AP

FILE - In this April 12, 1999 file photo, Dr. Richard Rockefeller...

FILE - In this April 12, 1999 file photo, Dr. Richard Rockefeller speaks at a news conference in Portland, Maine, about his family's pledge of $3.2 million to the Maine chapter of the Nature Conservancy for its purchase of land on the Upper St. John River. A family spokesman said Rockefeller was killed Friday, June 13, 2014, after crashing his small plane near the Westchester County Airport in Purchase, N.Y. Richard Rockfeller, of Falmouth, Maine, was a great grandson of Standard Oil co-founder John D. Rockefeller.
Photo: Robert F. Bukaty, AP